Is there a need for on-chip photonic integration for large data warehouse switches

Over the past 18-months VCSEL based optical engines have been integrated into package of large-scale HPC routers, moderate size Ethernet switches, and even FPGA´s. Competing solutions based on Silicon Photonics (SiP) are emerging and targeting similar application space but with better integration path through the use of TSV (Through Silicon Via) stack dies. Integrating either VCSEL or SiP based optical engines into complex IC package that operate at high temperatures and require high reliability is not trivial, and one should ask what is the technical or the economic advantage before embarking on such a drastic architectural change. We are currently investigating the extend to which scenarios on-chip photonic integration into large-scale data warehouse switches have clear power and/or bandwidth advantages over using traditional electrical I/O.